This invention relates to an improvement in a powder feeder in continuous casting.
The applicant has proposed a powder feeder in which each discharge port of a plurality of powder storage hoppers is connected to a final-stage powder container for mixing powder through a spring feeder. One end of the spring feeder is provided with an oscillating mechanism and is connected to the discharge port of the final-stage powder container, and the other end of the spring feeder meets the powder receiver in front of the final-stage powder container as a free end. The spring feeder is arranged so as to achieve return movement back and forth relative to the powder receiver (Japanese Patent Publication No. 57-54228).
The applicant has also proposed a tundish car on which is mounted a powder feeder equipped with a pair of spring feeders. The ends of pipe assemblies which extend from the base assemblies of the spring feeders swing horizontally back and forth in opposite directions near the strand nozzles, resulting in improved spreading of the casting powder (Japanese Patent Publication No. 61-11703).
However, the conventional powder feeder is arranged with the final-stage powder container at the same height as the work space of the mold. That is, since the end of the spring feeder provided with the oscillating mechanism is connected to the discharge port of the final-stage powder container, and the other end of the spring feeder meets as a free end to the powder receiver in front of the final-stage powder container, the final-stage powder container is inevitably placed at the same height as the mold and the tundish.
The final-stage powder container thus provided at the same height as the mold height is an obstacle to the casting operation. To remove this obstacle, the powder feeder including the final-stage powder container is arranged on the side opposite to the mold operator.
However, on the side of the continuous casting machine opposite to the operator, dust and molten steel are scattered. Under such conditions, maintenance work is very difficult and safety is a problem.
Furthermore, the relatively simple motion of swinging the conventional spring feeder results in a portion of the molten steel surface on which powder cannot be spread. This is called a dead angle. To remove this dead angle, precision machines must be used, but such use is difficult in the presence of scattered dust and molten steel. PG,5